<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<!--<input type="text" placeholder="请输入内容">-->
<!--<input type="radio">按钮1-->
<!--<input type="radio">按钮2-->
<!--<br>-->
<!--<input type="button" value="提交">-->

<h2>登录</h2>
<form>
    <div>
        <label for="username">用户名:</label>
        <input type="text" id="username" name="username" required>
    </div>
    <div>
        <label for="password">密码:</label>
        <input type="password" id="password" name="password" required>
    </div>
    <div>
        <select name="" id="">
            <option value="">老师</option>
            <option value="">学生</option>
        </select>
    </div>
    <div>
        <input type="submit" value="登录">
    </div>
</form>
</body>
</html>